We have a set of steps through our garden, underneath trees so it's always shady. They were re-laid last summer using nice stones and old bricks for the step edges, but already they are treacherous when there is any moisture at all, despite not having much visible growth on them.
A pressure washer would sort them out but the location makes this difficult and I'd prefer a way to treat the stone rather than scrub it.
Do products exist for this and if so, what are they and how are they used?I don't mean specific product endorsements, I'm not sure if I want weedkiller or moss killer or...